The present invention relates to a venetian blind cutting machine, and more particularly to a venetian blind cutting machine in which multiple replaceable dies and a cutting tool with multiple blades are used to complete cutting of the venetian blind while one single cylinder with reduced stroke is sufficient to control the cutting tool.
A venetian blind mainly includes an upper rail frame, a plurality of strips, and a lower frame. The upper rail frame, the strips, and the lower frame are sequentially connected to one another by cotton strings extending through them. Since the strips are made of thin and soft material, the whole venetian blind must be processed and cut with great care, lest it should be damaged before it becomes a finished product.
In the process of forming a venetian blind, it must be cut to a width which is the same as an actual width of the window for which the venetian blind is used. It is very troublesome to cut the upper rail frame and the lower frame. Both the upper rail frame and the lower frame are designed to have cross sections of fixed specifications. However, they are so different in their cross sectional shapes that they must be fabricated and cut with separate and different cutting apparatus. Furthermore, two groups of different dies and cutting tools must be separately designed for these two components with different sectional shapes, and the cutting apparatus are bulky in volume, resulting in a waste of resources.
Moreover, to cut a set of venetian blind, it is necessary to manually send the venetian blind to a rail frame cutting apparatus and then to a lower frame cutting apparatus. Such steps are repeated and doubtlessly consume a lot of labors. The thin and soft strips tend to be damaged during cutting and other fabricating processes. To improve the old method of fabricating venetian blinds, there was developed a venetian blind cutting machine which mainly includes a worktable supporting a die, and a cylinder for controlling a cutting tool corresponding to the die. Since a full set of venetian blind includes at least an upper rail frame, a plurality of strips, and a lower frame, the die mounted on the worktable must be provided with at least three fixing holes separately corresponding to the shapes of the upper rail frame, the strips, and the lower frame, so that the upper rail frame, the strips, and the lower frame may be separately extended through the fixing holes and be cut by the cylinder-controlled cutting tools.
Since there are various of different sectional shapes for the upper rail frame, the strip, and the lower frame, and since the numbers of the strips also have influence on the dimensions of the venetian blind, a plurality of dies must be cut to each contains a group of three fixing holes, so that one of these dies will fit for the upper rail frame, the strips, and the lower frame of a venetian blind to be cut. More specifically, when the upper rail frame, for example, is changed with the strips and the lower frame keeping unchanged, a completely different die must still be cut or prepared. This is the same in the event only the lower frame or the number or shape of the strips is changed.
In the above-described conventional venetian blind cutting machine, one single tool with only one blade is used to cut the upper rail frame, the strips, and the lower frame at a time. Thus, the blade of the cutting tool is usually badly worn after each cut. Meanwhile, a cylinder with a long stroke is required to control the tool that, of course, results in increased cost. And, when a big number of strips are included in the venetian blind to be cut, it is possible that a secondary cylinder controlling another cutting tool must be mounted below the worktable to help cut the venetian blind if the initial cylinder's stroke is not long enough to successfully complete the cut alone. These all result in increased costs for cylinders and cutting tools. In view of the drawbacks that result in high manufacturing cost of the conventional venetian blind cutting machine, it is therefore desirable to develop an improved venetian blind cutting machine to eliminate these drawbacks.